Tesla Report: Two-Thirds of all Tesla Model S Drivetrains Replaced by 60K Miles

A new study warns that two thirds of Tesla Model S cars will need to have their entire drivetrains replaced before they reach 60,000 miles.

Breitbart News reported in October, with Tesla’s stock plunging by -10 percent, that Consumer Reports had pulled its “best car ever” rating from Tesla’s Model S. Having received 1,400 responses from owners over the following month, who complained about a litany of squeaks, rattles, and multiple electric motor replacements, Consumer Reports (CR) pulled Tesla’s perfect 100-point score and revised the score for the new $127,820 Model S to a “worse than average” 43.

Tesla Motors on November 20 began a voluntary worldwide recall to inspect every one of the 90,000 Model S cars the company has built. Although the company claims that the motivation was seat belt safety problems, Breitbart News had already been reporting that Tesla’s unsustainable drivetrain had been known to insiders and owners for a long time.

Those fears seem to have been confirmed with the release of a Plug-In America study that out of 327 Model S cars analyzed, as many as two-thirds have had their drivetrains replaced before the car mileage hit 60,000, according to Green Car Reports.

The data was collected and processed using an industry standard “Weibull statistical analysis for probability distribution,” which estimates reliability lifetimes. The results map out the lifetime reliability for vehicle drivetrains that haven’t yet failed.

The study by a non-profit and very pro-industry group concluded that 77 drivetrains had failed compared to 250 “suspends,” or samples that haven’t yet failed.

Reliability engineers emphasized that the results were only valid if the data was correct. They had no selection bias, and the owner responses were completely random. Selection bias may have been in play, since only customers that knew about the survey filled it out. But the sample covered more than one percent of the about 25,000 total Model S made in 2012 and 2013.

The high replacement number of drivetrain replacements does not mean the Model S engines “failed,” because it is Tesla’s policy to replace them when they begin to make a very annoying noise. But if owners keep driving the car, they will suffer a catastrophic failure.

The Model S has had a very short lifespan, with the first customer deliveries beginning in mid-2012. But the car still represents the largest body of electric vehicles with greater than 100-mile range to date.

The study rated the Model S life expectancy at about 50,000 miles and predicts that the Telsa Model S will likely continue to have reliability issues with their earlier vehicles, which may negatively impact customer satisfaction.

There have been numerous comments on the Tesla Motors Club website voicing worries about the CR report and the risk to owners for expensive repair costs after their warranties expire. A number of owners claim that Tesla under warranty has had to replace the entire electric drive train on their Model S more than once.

The Tesla Model S warranty in 2012 was only 4 years or 50,000 mile-warranty, whichever comes first. Chairman Elon Musk extended the warranty in 2014 to 8 years and unlimited mileage. But with the cost of drivetrain replacement running at about $20,000, when the Model S warranties start expiring, the resale value may plummet.